“I was a diehard Giants fan,” Blank said in an exclusive interview yesterday. “I spent many a Sunday watching Sam Huff go at it with Jim Brown and the other great players of the day. If I wasn’t in front of a TV when the Giants were playing, then you can be sure I had my ear glued to a radio.”

What makes this NFC wild-card matchup even more bittersweet, Blank said, is the overwhelming admiration and gratefulness the 69-year-old co-founder of Home Depot feels to the Giants’ Mara and Tisch ownership families for easing his transition into the NFL in 2002.

The late Wellington Mara reached out to Blank and offered to do whatever was necessary to help, and that spirit of unity and commitment to the NFL inspired Blank to become the energetic presence in league circles he is today.

“The Maras and Tisches became a model for me,” said Blank, who backs up that statement by belonging to five NFL ownership committees (serving as chairman of two of them) and having team president Rich McKay play a prominent role in league affairs, too.

But only recently has Blank, a Stuyvesant High School graduate, been able to imitate what he considers the Giants’ enviable example of patience and franchise stability — and it took several memorable stumbles to get to that point.

From coddling Michael Vick almost right up until Vick went to prison on dogfighting charges (Blank famously was seen pushing Vick’s wheelchair on the sidelines after knee surgery) to the disastrous hiring of hot-name candidate Bobby Petrino as coach, Blank’s first seven years as Atlanta’s owner were rocky, to say the least.

The turnaround came with the hiring of Patriots personnel whiz Thomas Dimitroff as general manager and nice-guy Jaguars defensive coordinator Mike Smith as head coach while lucking into Boston College quarterback Matt Ryan with the No. 3 draft pick virtually within days of each other in 2008.

The Falcons since have reeled off four consecutive winning seasons and back-to-back playoff appearances for the first time in the team’s star-crossed history, and their 43-21 regular-season record in that span is the fifth-best in the league.

That’s the kind of success Blank expected when he lured Petrino from Louisville in 2007, only to see Petrino stab him in the back by slinking back to the college ranks at Arkansas just 13 games into his first season.

Asked about Petrino, Blank takes the high road, but still makes his point by praising the “honesty and forthrightness” of Smith, Petrino’s popular successor.

“It’s great to have a coach who is as honest as the day is long with the media, the front office and the players,” Blank said of Smith in what appeared to be a subtle shot at Petrino.

On the other hand, Blank’s “model” management group also has yet to win a playoff game — something the owner admits eats at him, especially in light of the two postseason victories and a 2004 NFC title-game appearance under Vick.

“I know that to be recognized as elite you have to be successful in the playoffs,” Blank said. “That’s one of the things the Giants have done, and we haven’t reached that level yet. We can’t call ourselves elite until we do. I like to call that a challenge, not a concern.”

What doesn’t concern Blank is any perception by Vick’s legion of fans in Atlanta that the owner made the wrong move in parting company with Vick once the player had served nearly two years in prison.

After taking Vick to arbitration to recoup part of the $37 million signing bonus Vick received in 2004 on the grounds he engaged in illegal activity, the Falcons cut him in June 2009 — paving the way for Vick’s rebirth in Philadelphia.

“I don’t think we had any choice in the way we handled Michael’s situation,” Blank said. “I tried to handle it the most respectful way for all parties. Michael’s done his time and has learned from his experiences, and I’m glad to see him back and performing at a very high level. He landed in the right place.”

Blank — who later switched his New York allegiance to the Jets after a chance meeting with Joe Namath on a golf course in 1967 — admits he won’t feel the same way about his own franchise until the current group gets over the postseason hump.

“Beating the Giants [tomorrow] would be a great place to start,” he said.